As described more fully in the above-identified application, a ski which is released from a ski boot on a slope, e.g. upon the falling of a skier, can engage in free flight and, at high speeds, poses a danger to other skiers. For this reason it has been proposed to provide the ski with an automatic brake which is retained in an inoperative position by application of the ski boot against the ski, e.g. against a spring force tending to bias an actuator into an inoperative position. The actuator may be engaged by the toe or heel of the ski boot when the latter is properly received in the ski binding.
The actuator is generally provided with one or two brake elements which can be constituted as blades and swing from their inoperative positions, in which they permit ordinary skiing, into operative positions in which they engage the ground and prevent further free flight of the ski when the actuator is released by the ski boot.
Such devices are termed hereinafter generically as ski brakes and, in one such ski brake, which is mounted behind the binding in a bearing or journal arrangement, the pivot axis includes an acute angle with the longitudinal axis of the ski and the basic spring force is generated by a torsion spring which acts upon a blade-like brake element.
In another conventional construction, leaf springs are secured at their forward ends to the ski and at their rearward ends tend to bend upwardly when they are unloaded. Upon loading by the ski boot, these spring elements are urged towards the upper surface of the ski to swing the blades into positions generally parallel to the ski edges as described in Austrian Pat. No. 299,036.
Other ski brakes are described in Austrian Pat. Nos. 280,867 and 210,804, although these devices are somewhat more remote from the present invention than the prior art devices described above and hence require no detailed discussion.
Austrian Pat. No. 305,844 describes a ski brake having a spring which, upon release of an actuator, rotates a shaft extending transversely to the ski about the shaft axis to bring the blade into play.
German published application (Offenlegungsschrift) No. 2,417,279 describes a ski brake which is mounted by a support plate on the upper surface of the ski. In one recess of this support plate, a circular-cross-section wire is pivotally journaled and is formed as one of two pivot shafts. One end of the circular-cross-section wire forms a brake spur while another region of the wire is bent into a retaining hoop, the free end of the hoop being formed as a second shaft journaled in a further recess of the support plate. It is important, in this construction, that the two journaling recesses in the support plate be exactly parallel, a factor which increases the fabrication cost and causes difficulties with respect to mounting or operation if precision is not achieved. These two journaling recesses impart an elastic prestress to the circular-cross-section wire so that the braking spur automatically springs into the operative position when the wire is released by the ski boot.